There are presently numerous different standards utilized in standard-definition and high-definition television systems used in studio production, post-production and distribution of television signals. As a result, a large number of incompatible interfaces exist for the interconnection and routing of component and composite digital video signals through a production, broadcast or post-production facility. For example, the 270 Mbit/s signal standard defined in SMPTE 125M-1992 has a different bandwidth than the 360-Mbit/s signal defined in SMPTE 267M-1995 or the 540-Mbit/s signal defined in SMPTE 293M-1996. The high definition television (HDTV) video signal format used in many television facilities has a bandwidth of 1.485 Gbit/s.
The interfaces utilized for each respective signal format are incompatible with the interfaces utilized for other signal formats. This results in redundancy in the case of facilities using more than one signal format in the distribution and routing infrastructure.
While a high-bandwidth link, such as that used for high-definition component video, contains sufficient bandwidth to carry multiple low-bandwidth component or composite video signals, the final multiplexed signal must comply with the signal format of the high-bandwidth link (i.e. high-definition component video) or it will be altered or blocked completely by equipment located in the link which expects a signal that is compliant with the standard high-bandwidth format. In addition, clock recovery information in each individual low-bandwidth signal must be restored after the signals are separated or the signals will be unusable.